Optical branching device with independent attenuation adjustment

Abstract

The utility model belongs to optical system, equipment technical field especially relates to the light splitting ratio adjustable optical branching device with independent attenuation adjustment, including pre -coupler, at least two post -coupler, the light output end of pre -coupler is connected the light input end of post -coupler through connecting optical fiber, the light output end of post -coupler connects output optical fiber, pre -coupler realizes one -level light splitting and will single -channel optical signal divide into multi -channel optical signal, and the light splitting ratio can be selected according to the need corresponding light splitting ratio and then adapt to different power distribution demand, the light signal of being light split enters attenuator, and the corresponding attenuation is adjusted independently, realizes the differentiating control of different road light power, and the two light signals after attenuation are respectively through the post -coupler of polarization maintaining optical fiber fusion draw taper technique again and divide into multi -channel independent optical signal and output, realize polarization maintaining light splitting, keep high extinction ratio and polarization stability, reduce the loss, promote consistency and reliability, reduce external environmental influence.

Description

Technical Field

[0001] This utility model belongs to the field of optical systems and equipment technology, and in particular relates to a beam splitter with adjustable splitting ratio and independent attenuation adjustment. Background Technology

[0002] Optical splitters are core passive devices in fiber optic links, used to proportionally distribute input optical signals to multiple outputs. For example, the patent publication CN220040805U, entitled "Variable Optical Attenuation Optical Splitter," mentions that by using an optical splitter chip to split the input optical signal into multiple outputs, and in conjunction with attenuators, not only can optical signals be obtained, but they can also meet the needs of various scenarios. However, optical splitters typically suffer from the following drawbacks when splitting into multiple outputs:

[0003] 1. The splitter has no polarization-maintaining capability, and the polarization state is easily distorted, making it unsuitable for polarization-sensitive systems;

[0004] 2. In multi-path polarization-maintaining coupling, polarization axis alignment is difficult, resulting in deterioration of extinction ratio and larger additional loss;

[0005] 3. Poor environmental adaptability; temperature or vibration can easily cause the spectrophotometer ratio to drift. Utility Model Content

[0006] To address the aforementioned problems and overcome the shortcomings of existing technologies, this utility model provides a splitter with an adjustable splitting ratio and independent attenuation adjustment.

[0007] The purpose of this invention is to provide an adjustable optical splitter with independent attenuation adjustment, which enables differentiated output of optical signal power, polarization-maintaining splitting, high extinction ratio and polarization stability, reduced loss, improved consistency and reliability, and reduced impact from the external environment.

[0008] To achieve the purpose of this utility model, the technical solution of this utility model is as follows:

[0009] An adjustable optical splitter with independent attenuation adjustment includes a pre-coupler and at least two post-couplers. The pre-coupler includes one optical input and at least two optical outputs, and the post-couplers include one optical input and at least two optical outputs. The optical output of the pre-coupler is connected to the optical input of the post-coupler via a connecting optical fiber, and the optical output of the post-coupler is connected to an output optical fiber. The optical output of the pre-coupler is connected to an attenuator via a connecting optical fiber. Taking a 1-to-4 adjustable optical splitter as an example, this invention first splits the light input from the light source output device into two paths using the pre-coupler, and then splits the light output from the pre-coupler into two paths, forming a cascaded coupling architecture using a first-stage 1-to-2 splitting link combined with a second-stage 2-to-4 splitting link. Combined with polarization-maintaining fiber fused biconical taper technology, it achieves the purpose of 1 polarization-maintaining light input and 4 polarization-maintaining light outputs.

[0010] Preferably, the output optical fiber of the post-coupler is provided with an output port.

[0011] Preferably, the pre-coupler and the post-coupler are fused tapered couplers, with the optical fiber inside the pre-coupler having a biconical coupling region and the optical fiber inside the post-coupler having a biconical coupling region.

[0012] Preferably, the attenuator is equipped with an attenuator plate, which is connected to a knob. Rotating the knob controls the depth at which the attenuator plate is inserted into the optical path.

[0013] Preferably, the optical input end of the precoupler is connected to an input optical fiber.

[0014] Preferably, the tunable optical splitter of this utility model further includes a housing, and the pre-coupler, attenuator, and post-coupler are arranged inside the housing.

[0015] Preferably, the encapsulation shell includes a housing, and inside the housing are a partition for fixing the pre-coupler and the post-coupler, and a mounting base for fixing the attenuator.

[0016] Preferably, a cable bundler is provided inside the housing, and the connecting optical fiber passes through the cable bundler.

[0017] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0018] 1. This utility model achieves first-stage beam splitting of an externally input light source through a pre-coupler using polarization-maintaining fiber fused biconical tapering (FBT) technology, dividing a single optical signal into multiple optical signals. The splitting ratio can be selected according to needs to adapt to different power distribution requirements. The split optical signals enter adjustable attenuators, and the corresponding attenuation amount can be adjusted independently to achieve differentiated control of the power of different optical paths. The attenuated optical signals are then split into multiple independent optical signals and output through a post-coupler using polarization-maintaining FBT technology, achieving polarization-maintaining beam splitting, maintaining a high extinction ratio and polarization stability, reducing loss, improving consistency and reliability, and reducing the impact of the external environment.

[0019] 2. The optical output terminal of the pre-coupler of this utility model outputs at least two optical signals, each of which is connected to an attenuator. By adjusting the attenuation of each optical signal, precise control is achieved, thereby realizing differentiated output of optical signal power and adapting to the power balance requirements of multiple channels.

[0020] 3. This utility model uses a package shell to integrate components such as the pre-coupler, post-coupler, and attenuator into a box-like structure. The connecting optical fiber is arranged inside the package shell, and only the input optical fiber for connecting to external light source output devices and the output optical fiber for output optical signals are outside the package shell. This allows the tunable optical splitter of this utility model to be mass-produced or used as a compact product. Attached Figure Description

[0021] Figure 1 This is a diagram showing the connection of the components of this utility model;

[0022] Figure 2 This is a schematic diagram of the internal structure of the packaging shell of this utility model.

[0023] In the picture:

[0024] 1. Light source output device; 2. Pre-coupler; 3. Attenuator; 4. Post-coupler; 5. Output port; 6. Encapsulation housing.

[0025] 61. Housing, 62. Closed door, 63. Partition, 64. Cable bundle, 65. Mounting base. Detailed Implementation

[0026] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0027] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to the present invention. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0028] Example 1

[0029] This embodiment is an adjustable optical splitter. This embodiment takes a 1-to-4 optical splitter as an example to explain in detail the structure and connection relationship of the optical splitter.

[0030] like Figure 1As shown, the optical splitter in this embodiment includes a two-stage coupler. The first-stage coupler is referred to here as the pre-coupler 2, and the second-stage coupler is referred to here as the post-coupler 4. The output light from the light source output device 1 first enters the pre-coupler 2 and then enters the post-coupler 4. The pre-coupler 2 includes one optical input end and two optical output ends, and the post-coupler 4 includes one optical input end and two optical output ends. The optical input end of the pre-coupler 2 is connected to an input optical fiber, which is directly connected to the light source output device 1. The optical output end of the pre-coupler 2 is connected to the optical input end of the post-coupler 4 through a connecting optical fiber. At the end, the optical output end of the rear coupler 4 is connected to the output optical fiber. The output optical fiber of the rear coupler 4 has an output port 5. Between the front coupler 2 and the rear coupler 4, the optical fiber connecting the optical output end of the front coupler 2 is connected to the attenuator 3. The front coupler 2 first splits the light input from the light source output device 1 into two paths. After passing through the attenuator 3, the light output from the front coupler 2 is split into two paths again, forming a cascaded coupling architecture that uses a first-level 1-to-2 distribution link combined with a second-level 2-to-4 distribution link. Combined with polarization-maintaining fiber fused taper technology, it achieves the purpose of 1 polarization-maintaining light input and 4 polarization-maintaining light output.

[0031] From a structural perspective, both the pre-coupler 2 and the post-coupler 4 in this embodiment are fused biconical coupling couplers. The optical fiber inside the pre-coupler 2 has a biconical coupling region, and the optical fiber inside the post-coupler 4 also has a biconical coupling region. In this embodiment, the pre-coupler 2 and the post-coupler 4 can split into two paths according to a specific ratio corresponding to the splitting ratio. The coating layers of the two optical fibers are removed, and they are placed closely side by side. They are melted and softened under a high-temperature flame, and simultaneously stretched to both ends to form a biconical coupling region. At the thinnest part of the cone region, the core diameter is extremely small, and the light is no longer confined within the core but diffuses into the cladding to form an evanescent field. The evanescent fields of the two optical fibers overlap each other, and the light energy is coupled and transferred between the optical fibers through mode interference. Furthermore, by precisely controlling parameters such as the stretching length, flame temperature, speed, and angle, the energy transfer ratio is determined, thereby creating arbitrary splitting ratios such as 50:50, 90:10, and 99:1.

[0032] In this embodiment, attenuator 3 can be a polarization-maintaining fiber attenuator 3. This attenuator 3 is a device that can precisely reduce optical power while strictly maintaining the polarization state of the input light. Attenuator 3 has an attenuation plate inside, connected to a knob. Rotating the knob controls the depth of the attenuator's insertion into the optical path, thus controlling the light energy absorption ratio. The attenuator can be a neutral density filter, used in conjunction with a collimator to achieve a large attenuation range of 0 to -60 dB, high precision between -0.1 dB and 0.1 dB, and a high extinction ratio greater than 20 dB. The optical output of the precoupler 2... Attenuators 3 are arranged on the connecting optical fibers at both ends, so that the attenuation of each path can be adjusted independently to achieve power differentiation control of the two branches. For example, after the input of an external 1550nm light source, the single optical signal is split into two paths through a first-stage fused tapered coupler. The splitting ratio is customized according to the needs to adapt to different power distribution requirements. Then, through the independent power differentiation control of attenuator 3, it adapts to the multi-channel power balance requirements. The two optical signals after attenuation are then output as four independent optical signals through a second-stage fused tapered coupler, completing the 1-to-4 splitting function.

[0033] In this embodiment, polarization-maintaining fiber can be used. Polarization-maintaining light, also known as polarized light transmitted through polarization-maintaining fiber, refers to light that can stably maintain its polarization state without random changes when transmitted in polarization-maintaining fiber. It solves the core problem of polarization state being easily interfered with and randomly drifting in ordinary optical fibers, thus making it suitable for polarization-sensitive systems such as fiber optic gyroscopes and coherent communication.

[0034] The input of the optical splitter in this embodiment can be polarization-maintaining fiber FC / APC, and the output port 5 can be an FC flange. In actual tests, the light source output device 1 outputs -7dBm light. After passing through the optical splitter of this embodiment, it can output two -60dBm light, one of which is -59.7dBm and the other is -59.5dBm. It can also output two -5.7dBm light, one of which is -5.69dBm and the other is -5.75dBm. In other test examples, the output can be adjusted between 0 and -60dBm.

[0035] Example 2

[0036] Example 1 details the connection relationships and coordination schemes of components such as pre-coupler 2, post-coupler 4, and attenuator 3. The components and their corresponding connecting optical fibers are scattered together and cannot be used as a whole product. However, the light source output device 1 is used as an independent component. In this example, the components in Example 1 are assembled into a whole product to form a dimmable splitter, which is convenient to connect with the light source output device 1 and is also convenient for mass production or use.

[0037] like Figure 2As shown, the tunable optical splitter of this embodiment includes a housing 6, and components such as a pre-coupler 2, an attenuator 3, and a post-coupler 4 are arranged inside the housing 6 to form a box-like structure. Only the input optical fiber connected to the optical input end of the pre-coupler 2, the connector, and the output port 5 are exposed outside the housing 6. The overall structure is compact and the internal components are restricted and protected.

[0038] As a specific implementation plan, such as Figure 2 As shown, the encapsulation shell 6 includes a shell 61 with connecting seats at its four corners. A cover plate is mounted on the shell 61, and the cover plate is connected to the connecting seats by bolts and screws to form an encapsulation structure. Inside the shell 61 are partitions 63 for fixing the pre-coupler 2 and the post-coupler 4, and a fixing seat 65 for fixing the attenuator 3. Specifically, there are multiple partitions 63 with gaps between them. The pre-coupler 2 and the post-coupler 4 are arranged within the gaps in the partitions 63. In a more specific embodiment, a locking block is mounted on the partition 63, and the locking block has a locking groove. The locking block is mounted on the partition 63, and the locking block connects with the locking groove to form a locking structure. The pre-coupler 2 and the post-coupler 4 abut against the lower end of the locking block or have a small gap, thus confining the coupler within the gaps in the partitions 63. In another more specific embodiment, special adhesive tape can be used to attach the coupler and the corresponding connecting optical fiber to the encapsulation shell 6 to achieve the confinement of the coupler and connecting optical fiber. Alternatively, a fixing base 65 is connected to the encapsulation shell 6. The fixing base 65 has a through hole, and the attenuator 3 is installed in the through hole. In addition, a cable tie 64 is arranged inside the shell 61. There are gaps between the cable tie 64 and the inner wall of the side plate and the inner wall of the bottom plate, so that the connecting optical fiber can pass through the cable tie 64. There are multiple cable ties 64. From the arrangement scheme, the cable ties 64 are arranged on the inner wall of the side plate of the encapsulation shell 6, which are referred to here as side plate cable ties. Cable ties are also arranged between the partition 63, the fixing base 65 and the side plate cable ties 64. 64. The cable tie 64 is arranged on the inner wall of the base plate and is referred to here as the base plate cable tie. The connecting optical fiber in the encapsulation shell 6 can not only pass through the gaps between multiple partitions 63, but also pass through the base plate cable tie and the side plate cable tie, so that the connecting optical fiber is arranged in a bent position at the turning point and in a straight position at the extension point. The connecting optical fiber is fixed with the assistance of special tape. For example, the special tape can be connected to the base plate. In addition, the base plate or side plate cable tie 64 has an arc-shaped limiting plate, so that the connecting optical fiber is arranged along the arc-shaped limiting plate at the bending point.

[0039] The side panel of the housing 61 in this embodiment has a closed door 62. Specifically, the inner wall of the side panel has a bent plate, which is bent to form a through groove. The wing plates on both sides of the closed door 62 are arranged in the through groove to form a door structure that can move up and down. Through holes can be opened on the closed door 62 to ensure that the input optical fiber passes through the through holes. After the cover plate is connected to the housing 61, the cover plate presses down on the closed door 62, which can also prevent the input optical fiber from retracting into the encapsulation housing 6. The output port 5 can be an FC flange and installed on the side panel of the housing 61.

[0040] Although the specific embodiments of the present utility model have been described above in conjunction with the accompanying drawings, this is not intended to limit the scope of protection of the present utility model. Those skilled in the art should understand that various modifications or variations that can be made by those skilled in the art without creative effort based on the technical solution of the present utility model are still within the scope of protection of the present utility model.

Claims

1. A splitter with independently adjustable attenuation ratio, characterized in that, Includes a front coupler (2) and at least two rear couplers (4); The pre-coupler (2) includes one optical input terminal and at least two optical output terminals, and the post-coupler (4) includes one optical input terminal and at least two optical output terminals; The optical output end of the pre-coupler (2) is connected to the attenuator (3) via a connecting optical fiber. The attenuator (3) is connected to the optical input end of the post-coupler (4) via a connecting optical fiber. The optical output end of the post-coupler (4) is connected to the output optical fiber.

2. The tunable splitter with independent attenuation adjustment according to claim 1, characterized in that, The output fiber of the rear coupler (4) is provided with an output port (5).

3. The tunable splitter with independent attenuation adjustment according to claim 1, characterized in that, The front coupler (2) and the rear coupler (4) are fused tapered couplers.

4. The tunable splitter with independent attenuation adjustment according to claim 3, characterized in that, The internal optical fiber of the pre-coupler (2) has a biconical coupling region.

5. The tunable splitter with independent attenuation adjustment according to claim 3, characterized in that, The internal optical fiber of the rear coupler (4) has a biconical coupling region.

6. The tunable splitter with independent attenuation adjustment according to claim 1, characterized in that, The attenuator (3) is equipped with an attenuator plate inside. The attenuator plate is connected to a knob. Rotating the knob controls the depth to which the attenuator plate is inserted into the optical path.

7. The tunable splitter with independent attenuation adjustment according to claim 1, characterized in that, The optical input end of the pre-coupler (2) is connected to an input optical fiber.

8. The tunable splitter with independent attenuation adjustment according to claim 1, characterized in that, It also includes a package housing (6), a front coupler (2), an attenuator (3), and a rear coupler (4) arranged inside the package housing (6).

9. The tunable splitter with independent attenuation adjustment according to claim 8, characterized in that, The encapsulation shell (6) includes a shell (61), and a partition (63) for fixing the front coupler (2) and the rear coupler (4) and a mounting base (65) for fixing the attenuator (3) are provided inside the shell (61).

10. The tunable splitter with independent attenuation adjustment according to claim 9, characterized in that, A cable tie (64) is provided inside the housing (61), and the connecting optical fiber passes through the cable tie (64).

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